The African National Congress (ANC) launched its appeal against an interdict on singing "shoot the boer" on Thursday, but its call to exercise "restraint" in singing the lyrics remained in force, it said in a statement.

"We find it very unfortunate that when the court heard the matter and came to the unconstitutional finding, the ANC, an interest party central to the matter was neither alerted nor allowed to make an input."

The party "restrained" its members from singing the lyrics "shoot the boer", a chant by a former Youth League president Peter Mokaba, which was inserted in a liberation song "Ayesaba amagwala" (the cowards are afraid).

Afrikaner lobby group Afriforum successfully received an interdict from the High Court in Johannesburg last week on the singing of the three words, pending the hearing of a hate speech application to the Equality Court, which is due to begin on May 3.

The ANC believes that the court erred in banning the words in question "irrespective of the time, place, manner and context in which the words are uttered, published or chanted".

The court also failed to consider the Constitutional guarantee of freedom of expression, and that any action should have been directed to the Equality Court.

The ANC also wants the judge to supply reasons for his judgment, and they will be a supplement to Thursday's application.

The action was not related to Wednesday's call for restraint.

"The call made remains in force."

ANC Youth League president Julius Malema pushed the lyrics into the limelight by singing them at a student gathering in Johannesburg in March.

Debate over whether it is a liberation song that should not be taken literally, or whether it incites the murder of farmers came to a head when AWB leader Eugene Terre'Blanche was beaten to death on his farm in Ventersdorp on Saturday.